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1.
Chemosphere ; 350: 141104, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38171400

RESUMO

The loss of active components, weak acid resistance, and low recover efficiency of common Ca-based catalysts limited its further development and application. In this study, to effectively produce biodiesel from waste cooking oil (WCO), a green and recyclable magnetic acid-base bifunctional CoFe/biochar/CaO catalyst was prepared from sargassum and river snail shell waste via hydrothermal method. The catalysts' structure and properties were investigated by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), CO2/NH3 temperature programmed desorption (CO2/NH3 TPD), etc., The prepared catalyst mainly consisted of the carbon skeleton, CoFe alloy, and CaO. CoFe alloy provided catalyst's ferromagnetism for magnetic separation as well as acid sites for transesterification of WCO. Ca and other metal species with nanoscale (∼5.64 nm) were dispersively anchored on sargassum biochar surface, thereby leading to good catalytic activity (99.21% biodiesel yield) and stability (91.70% biodiesel yield after the 5th cycle). In addition, response surface methodology-Box-Behnken design (RSM-BBD) revealed the optimal operational conditions were 16:1 methanol/oil molar ratio, 3 wt% catalyst dosage, 73 °C for 157 min. The maximum biodiesel yield predicted value was 98.29% and the experimental value was 99.21%, indicating good satisfaction of the established model. Moreover, the quality of WCO biodiesel met the ASTM D6751 standards. This study benefits magnetic waste-derived acid-base bifunctional catalysts for the disposal of WCO towards sustainable biodiesel production.


Assuntos
Biocombustíveis , Carvão Vegetal , Óleos de Plantas , Óleos de Plantas/química , Biocombustíveis/análise , Dióxido de Carbono , Esterificação , Culinária , Catálise , Ligas , Fenômenos Magnéticos
2.
Proc Natl Acad Sci U S A ; 118(11)2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33836585

RESUMO

The alteration of the enteric nervous system (ENS) and its role in neuroimmune modulation remain obscure in the pathogenesis of inflammatory bowel diseases (IBDs). Here, by using the xCell tool and the latest immunolabeling-enabled three-dimensional (3D) imaging of solvent-cleared organs technique, we found severe pathological damage of the entire ENS and decreased expression of choline acetyltransferase (ChAT) in IBD patients. As a result, acetylcholine (ACh), a major neurotransmitter of the nervous system synthesized by ChAT, was greatly reduced in colon tissues of both IBD patients and colitis mice. Importantly, administration of ACh via enema remarkably ameliorated colitis, which was proved to be directly dependent on monocytic myeloid-derived suppressor cells (M-MDSCs). Furthermore, ACh was demonstrated to promote interleukin-10 secretion of M-MDSCs and suppress the inflammation through activating the nAChR/ERK pathway. The present data reveal that the cholinergic signaling pathway in the ENS is impaired during colitis and uncover an ACh-MDSCs neuroimmune regulatory pathway, which may offer promising therapeutic strategies for IBDs.


Assuntos
Acetilcolina/administração & dosagem , Sistema Nervoso Entérico/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Doenças Inflamatórias Intestinais/terapia , Interleucina-10/metabolismo , Monócitos/metabolismo , Células Supressoras Mieloides/metabolismo , Receptores Nicotínicos/metabolismo , Acetilcolina/farmacologia , Animais , Colina O-Acetiltransferase/metabolismo , Sistema Nervoso Entérico/fisiopatologia , Feminino , Humanos , Doenças Inflamatórias Intestinais/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo
3.
J Neuroinflammation ; 15(1): 290, 2018 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-30333036

RESUMO

BACKGROUND: PD-L1 is an immune inhibitory receptor ligand that leads to T cell dysfunction and apoptosis by binding to its receptor PD-1, which works in braking inflammatory response and conspiring tumor immune evasion. However, in gliomas, the cause of PD-L1 expression in the tumor microenvironment is not yet clear. Besides, auxiliary biomarkers are urgently needed for screening possible responsive glioma patients for anti-PD-1/PD-L1 therapies. METHODS: The distribution of tumor-infiltrating T cells and PD-L1 expression was analyzed via immunofluorescence in orthotopic murine glioma model. The expression of PD-L1 in immune cell populations was detected by flow cytometry. Data excavated from TCGA LGG/GBM datasets and the Ivy Glioblastoma Atlas Project was used for in silico analysis of the correlation among genes and survival. RESULTS: The distribution of tumor-infiltrating T cells and PD-L1 expression, which parallels in murine orthotopic glioma model and human glioma microdissections, was interrelated. The IFN-γ level was positively correlated with PD-L1 expression in murine glioma. Further, IFN-γ induces PD-L1 expression on primary cultured microglia, bone marrow-derived macrophages, and GL261 glioma cells in vitro. Seven IFN-γ-induced genes, namely GBP5, ICAM1, CAMK2D, IRF1, SOCS3, CD44, and CCL2, were selected to calculate as substitute indicator for IFN-γ level. By combining the relative expression of the listed IFN-γ-induced genes, IFN-γ score was positively correlated with PD-L1 expression in different anatomic structures of human glioma and in glioma of different malignancies. CONCLUSION: Our study identified the distribution of tumor-infiltrating T cells and PD-L1 expression in murine glioma model and human glioma samples. And we found that IFN-γ is an important cause of PD-L1 expression in the glioma microenvironment. Further, we proposed IFN-γ score aggregated from the expressions of the listed IFN-γ-induced genes as a complementary prognostic indicator for anti-PD-1/PD-L1 therapy.


Assuntos
Antígeno B7-H1/metabolismo , Neoplasias Encefálicas , Linfócitos T CD8-Positivos/patologia , Glioma , Interferon gama/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Microambiente Tumoral/fisiologia , Animais , Antígeno B7-H1/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Proteínas de Ligação ao Cálcio/metabolismo , Células Cultivadas , Técnicas de Cocultura , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioma/metabolismo , Glioma/patologia , Glioma/terapia , Interferon gama/farmacologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas dos Microfilamentos/metabolismo , Microglia/fisiologia , Receptor de Morte Celular Programada 1/genética , RNA Mensageiro/metabolismo , Microambiente Tumoral/efeitos dos fármacos
4.
Cell Mol Immunol ; 8(4): 359-67, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21572449

RESUMO

Trichosanthin (TCS), extracted from the Chinese medicinal herb Trichosanthes kirilowi, has shown promise for the inhibition of tumor growth. However, its immunomodulatory effect on tumor-host interaction remains unknown. In this study, we focused on the effect of TCS on murine anti-tumor immune response in the 3LL Lewis lung carcinoma tumor model and explored the possible molecular pathways involved. In addition to inhibiting cell proliferation and inducing apoptosis in the 3LL tumor, TCS retarded tumor growth and prolonged mouse survival more significantly in C57BL/6 immunocompetent mice than in nude mice. This reflected the fact that the host immune system was involved in tumor eradication. Using FACS analysis, we found that TCS increased the percentage of effector T cells, particularly Interferon-gamma (IFN-γ) producing CD4(+) and CD8(+) T cells from tumor-bearing mice. TCS also promoted the vigorous proliferation of antigen-specific effector T cells, markedly increased Th1 cytokine secretion and elicited more memory T cells in tumor-bearing mice, consequently enhancing the anti-tumor response and inducing immune protection. Furthermore, we found that TCS upregulated the expression of tumor suppressor in lung cancer 1 (TSLC1) in 3LL tumor cells and the expression of its ligand, class I-restricted T cell-associated molecule (CRTAM), in effector T cells. Blocking TSLC1 expression with small interfering RNA (siRNA) significantly eliminated the effects of TCS on the proliferation and cytokine secretion of effector T cells, suggesting that TCS enhances anti-tumor immune response at least partially by boosting the interaction between TSLC1 and CRTAM. Collectively, our data demonstrate that TCS not only affects tumor cells directly, but also enhances anti-tumor immunity via the interaction between TSLC1 and CRTAM. These findings may lead to the development of a novel approach for tumor regression.


Assuntos
Carcinoma Pulmonar de Lewis/tratamento farmacológico , Carcinoma Pulmonar de Lewis/imunologia , Moléculas de Adesão Celular/imunologia , Moléculas de Adesão Celular/metabolismo , Imunoglobulinas/imunologia , Imunoglobulinas/metabolismo , Tricosantina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/metabolismo , Carcinoma Pulmonar de Lewis/metabolismo , Molécula 1 de Adesão Celular , Moléculas de Adesão Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Feminino , Imunoglobulinas/genética , Interferon gama/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , RNA Interferente Pequeno/farmacologia , Células Th1/efeitos dos fármacos , Células Th1/metabolismo , Tricosantina/imunologia
5.
PLoS One ; 6(2): e17164, 2011 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-21359178

RESUMO

T(H)17 cells have been implicated in a growing list of inflammatory disorders. Antagonism of T(H)17 cells can be used for the treatment of inflammatory injury. Currently, very little is known about the natural compound controlling the differentiation of T(H)17 cells. Here, we showed that Baicalin, a compound isolated from a Chinese herb, inhibited T(H)17 cell differentiation both in vitro and in vivo. Baicalin might inhibit newly generated T(H)17 cells via reducing RORγt expression, and together with up-regulating Foxp3 expression to suppress RORγt-mediated IL-17 expression in established T(H)17 cells. In vivo treatment with Baicalin could inhibit T(H)17 cell differentiation, restrain T(H)17 cells infiltration into kidney, and protect MRL/lpr mice against nephritis. Our findings not only demonstrate that Baicalin could control T(H)17 cell differentiation but also suggest that Baicalin might be a promising therapeutic agent for the treatment of T(H)17 cells-mediated inflammatory diseases.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Flavonoides/farmacologia , Sistema Imunitário/efeitos dos fármacos , Células Th17/efeitos dos fármacos , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Avaliação Pré-Clínica de Medicamentos , Regulação da Expressão Gênica/efeitos dos fármacos , Sistema Imunitário/citologia , Sistema Imunitário/metabolismo , Fatores Imunológicos/farmacologia , Interleucina-6/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos MRL lpr , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Células Th17/metabolismo , Células Th17/fisiologia , Fator de Crescimento Transformador beta/farmacologia
6.
Vaccine ; 23(44): 5160-7, 2005 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-16040168

RESUMO

Vitamin A deficiency diminishes Th2-mediated Ab responses. Providing Vitamin A or its active metabolites reverses this defect. All-trans retinoic acid (ATRA), an acid derivation of Vitamin A, regulates the balance of immune response induced by TR421-hCGbeta DNA vaccine. Compared to DNA vaccine alone or treatment with vehicle, significantly higher level of antibody against the protein encoded by DNA vaccine was observed in mice 6 weeks after the first immunization. The IgG2a/IgG1 ratio was lower in mice treated with ATRA. We also found that treatment with ATRA also diminishes specific cellular immune response induced by gene immunization by measuring the marker of cellular immune response. We conclude that ATRA biases the immune response to Th2 direction induced by DNA vaccine and acts as a candidate adjuvant and immunomodulatory molecule.


Assuntos
Gonadotropina Coriônica Humana Subunidade beta/imunologia , Células Th2/efeitos dos fármacos , Tretinoína/farmacologia , Vacinas de DNA/imunologia , Animais , Camundongos , Camundongos Endogâmicos BALB C , Células Th2/imunologia , Tretinoína/administração & dosagem , Vacinas de DNA/administração & dosagem
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